In WO 96/30347, the preparation of [6,7-Bis(2-methoxy-ethoxy)-quinazolin-4-yl]-(3-ethynyl-phenyl)amine hydrochloride as well as the uses of this compound have been disclosed. This compound is depicted in formula (I).

In particular, this compound is an inhibitor of tyrosine kinase enzymes such as epidermal growth factor receptors and can be used for the treatment and/or prevention of diseases which are associated with tyrosine kinase enzymes such as epidermal growth factor receptors, such as cancer, particularly non small cell lung cancer, colorectal cancer, refractory non small cell lung cancer, pancreatic cancer, ovarian cancer, breast cancer, glioma, head cancer or neck cancer.
Recently, two different polymorphs of [6,7-bis(2-methoxy-ethoxy)-quinazolin-4-yl]-(3-ethynyl-phenyl)amine hydrochloride, designated as polymorph A and polymorph B, have been disclosed in WO 01/34574.
Polymorphism is defined as the ability of a substance to crystallize in more than one crystal lattice arrangement. Polymorphism can influence many aspects of solid state properties of a drug. Different crystal modifications of a substance may differ considerably from one another in many respects such as their solubility, dissolution rate and finally bioavailability. An exhaustive treatment of polymorphism in pharmaceutical and molecular crystals is given e.g., by Byrn (Byrn, S. R., Pfeiffer, R. R., Stowell, J. G., “Solid-State Chemistry of Drugs”, SSCI Inc., West Lafayette, Ind., 1999), Brittain, H. G., “Polymorphism in Pharmaceutical Solids”, Marcel Dekker, Inc., New York, Basel, 1999) or Bernstein (Bernstein, J., “Polymorphism in Molecular Crystals”, Oxford University Press, 2002).
Of the two polymorphs described in WO 01/34574, polymorph B is thermodynamically more stable than polymorph A, while polymorph A exhibits a better solubility and dissolution rate than polymorph B. However, based on the known polymorphs A and B of [6,7-Bis(2-methoxy-ethoxy)-quinazolin-4-yl]-(3-ethynyl-phenyl)amine hydrochloride, it was still considered desirable to have a form of this compound which, while being thermodynamically more stable than polymorph A, also exhibits a better solubility and dissolution rate than polymorph B.